In children with a history of convulsions, especially those caused by brain dysplasia, try to avoid vaccination against epidemic encephalitis or encephalitis B. These two vaccines are prohibited, as they may cause fever and convulsions in children after vaccination. These two vaccines are prohibited, so as not to cause the emergence of convulsions in children after vaccination with these vaccines, and even cause fever, convulsions and other adverse reactions in children. Because the B-encephalitis vaccine is a viral vaccine developed by the B-encephalitis virus, and the influenza vaccine is a bacterial vaccine, these vaccines can cause mild brain infections in children, especially for children with a history of convulsions.